Carpenters, masons and other persons in the building trades use a variety of tools in practicing their craft. For example, carpenters and masons use a tool known as a level to help assure that walls are vertical and that floors are horizontal. A leading manufacturer of high-quality builder's tools is Empire Level Mfg. Corp. of Milwaukee, Wis.
Another type of builder's tool is known as a rafter square. A rafter square is triangular in shape, has two edges at right angles to one another and has markings on it. Such markings are used by a carpenter in cutting lumber, e.g., roof joists and the like, to obtain a particular roof "pitch," e.g., 12 to 1, 10 to 1 or the like. (A roof having an exemplary 12 to 1 pitch has a vertical rise of 1 unit of measure, one inch for example, for each horizontal dimension (or "run") of 12 units of measure, e.g., twelve inches.
Rafter squares of known types are made by molding plastic or by die casting metal such as aluminum. While such rafter squares have been and are generally suitable for the intended purpose, they are not without disadvantages. Molded plastic rafter squares are not as durable as metal squares. And if the linear and angular dimensional markings are applied using paint or similar material, such markings are likely to wear off rather quickly.
Die cast rafter squares are inherently more durable than plastic squares but they have a disadvantage of their own. Die cast squares tend to be brittle and break easily. And making a die cast rafter square (or, for that matter, any die cast object) involves placing molten metal into a shaping die. Handling molten metal is attended by a certain level of danger not present with other manufacturing methods.
And die cast rafter squares are, in view of the invention, relatively expensive to make. Of course, a higher manufactured cost usually translates into a higher user purchase price.
A new method for making a builder's tool, e.g., a rafter square, which addresses problems and shortcomings of the prior art would be an important technical advance.